Modern plants and manufacturing facilities use a great number of electrically or electromagnetically controlled (most often hydraulic and/or pneumatic) actuators in their operation.
These actuators are generally provided with multi-pole contact units, each with a ground contact, and if required by regulation, with a safety contact and at least one control contact over which the control signals are transmitted for the control of the actuator.
Each of the multi-pole contact units is in this case connected electrically via a multi-wire cable to a central control or switching box from which they are supplied with the necessary control signals in accordance with applicable plant control or regulating requirements. The multi-lead cables are then generally connected to the multi-pole contact units assigned to them by means of corresponding multi-pole plug units.
Long cable sections which have to be laid over great distances to the central terminal box or central control or switching box are necessary, especially if several such multi-pole contact units are installed. In modern manufacturing plants for motor vehicles assembly, for example, two multi-pole contact units are provided for each one of sometimes 10,000 or more actuating and control units. In such plants, an extraordinary amount of cabling is therefore used and extraordinary costs pertaining to the central terminal box or to the central control or switching box are involved.
Failure detection within the cabling arrangement is difficult and time consuming because of the multitude of lines and line connections, especially when such production plants are started up or re-started.
Against this background, it is the object of the instant invention to reduce the overall expenditure for such cabling, to improve the accessibility of the cabling and to facilitate failure detection.